FFmpeg: libavcodec/yop.c Source File

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yop.c
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1 /*
2  * Psygnosis YOP decoder
3  *
4  * Copyright (C) 2010 Mohamed Naufal Basheer <naufal11@gmail.com>
5  * derived from the code by
6  * Copyright (C) 2009 Thomas P. Higdon <thomas.p.higdon@gmail.com>
7  *
8  * This file is part of FFmpeg.
9  *
10  * FFmpeg is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public
12  * License as published by the Free Software Foundation; either
13  * version 2.1 of the License, or (at your option) any later version.
14  *
15  * FFmpeg is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18  * Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with FFmpeg; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23  */
24 
25 #include <string.h>
26 
27 #include "libavutil/imgutils.h"
28 #include "libavutil/internal.h"
29 #include "libavutil/intreadwrite.h"
30 
31 #include "avcodec.h"
32 #include "internal.h"
33 
34  typedef struct YopDecContext {
35   AVCodecContext *avctx;
36   AVFrame *frame;
37 
38   int num_pal_colors;
39   int first_color[2];
40   int frame_data_length;
41 
42   uint8_t *low_nibble;
43   uint8_t *srcptr;
44   uint8_t *src_end;
45   uint8_t *dstptr;
46   uint8_t *dstbuf;
47 } YopDecContext;
48 
49 // These tables are taken directly from:
50 // http://wiki.multimedia.cx/index.php?title=Psygnosis_YOP
51 
52 /**
53  * Lookup table for painting macroblocks. Bytes 0-2 of each entry contain
54  * the macroblock positions to be painted (taken as (0, B0, B1, B2)).
55  * Byte 3 contains the number of bytes consumed on the input,
56  * equal to max(bytes 0-2) + 1.
57  */
58  static const uint8_t paint_lut[15][4] =
59  {{1, 2, 3, 4}, {1, 2, 0, 3},
60  {1, 2, 1, 3}, {1, 2, 2, 3},
61  {1, 0, 2, 3}, {1, 0, 0, 2},
62  {1, 0, 1, 2}, {1, 1, 2, 3},
63  {0, 1, 2, 3}, {0, 1, 0, 2},
64  {1, 1, 0, 2}, {0, 1, 1, 2},
65  {0, 0, 1, 2}, {0, 0, 0, 1},
66  {1, 1, 1, 2},
67  };
68 
69 /**
70  * Lookup table for copying macroblocks. Each entry contains the respective
71  * x and y pixel offset for the copy source.
72  */
73  static const int8_t motion_vector[16][2] =
74  {{-4, -4}, {-2, -4},
75  { 0, -4}, { 2, -4},
76  {-4, -2}, {-4, 0},
77  {-3, -3}, {-1, -3},
78  { 1, -3}, { 3, -3},
79  {-3, -1}, {-2, -2},
80  { 0, -2}, { 2, -2},
81  { 4, -2}, {-2, 0},
82  };
83 
84  static av_cold int yop_decode_close(AVCodecContext *avctx)
85 {
86  YopDecContext *s = avctx->priv_data;
87 
88  av_frame_free(&s->frame);
89 
90  return 0;
91 }
92 
93  static av_cold int yop_decode_init(AVCodecContext *avctx)
94 {
95  YopDecContext *s = avctx->priv_data;
96  s->avctx = avctx;
97 
98  if (avctx->width & 1 || avctx->height & 1 ||
99  av_image_check_size(avctx->width, avctx->height, 0, avctx) < 0) {
100  av_log(avctx, AV_LOG_ERROR, "YOP has invalid dimensions\n");
101  return AVERROR_INVALIDDATA;
102  }
103 
104  if (avctx->extradata_size < 3) {
105  av_log(avctx, AV_LOG_ERROR, "Missing or incomplete extradata.\n");
106  return AVERROR_INVALIDDATA;
107  }
108 
109  avctx->pix_fmt = AV_PIX_FMT_PAL8;
110 
111  s->num_pal_colors = avctx->extradata[0];
112  s->first_color[0] = avctx->extradata[1];
113  s->first_color[1] = avctx->extradata[2];
114 
115  if (s->num_pal_colors + s->first_color[0] > 256 ||
116  s->num_pal_colors + s->first_color[1] > 256) {
117  av_log(avctx, AV_LOG_ERROR,
118  "Palette parameters invalid, header probably corrupt\n");
119  return AVERROR_INVALIDDATA;
120  }
121 
122  s->frame = av_frame_alloc();
123  if (!s->frame)
124  return AVERROR(ENOMEM);
125 
126  return 0;
127 }
128 
129 /**
130  * Paint a macroblock using the pattern in paint_lut.
131  * @param s codec context
132  * @param tag the tag that was in the nibble
133  */
134  static int yop_paint_block(YopDecContext *s, int linesize, int tag)
135 {
136  if (s->src_end - s->srcptr < paint_lut[tag][3]) {
137  av_log(s->avctx, AV_LOG_ERROR, "Packet too small.\n");
138  return AVERROR_INVALIDDATA;
139  }
140 
141  s->dstptr[0] = s->srcptr[0];
142  s->dstptr[1] = s->srcptr[paint_lut[tag][0]];
143  s->dstptr[linesize] = s->srcptr[paint_lut[tag][1]];
144  s->dstptr[linesize + 1] = s->srcptr[paint_lut[tag][2]];
145 
146  // The number of src bytes consumed is in the last part of the lut entry.
147  s->srcptr += paint_lut[tag][3];
148  return 0;
149 }
150 
151 /**
152  * Copy a previously painted macroblock to the current_block.
153  * @param copy_tag the tag that was in the nibble
154  */
155  static int yop_copy_previous_block(YopDecContext *s, int linesize, int copy_tag)
156 {
157  uint8_t *bufptr;
158 
159  // Calculate position for the copy source
160  bufptr = s->dstptr + motion_vector[copy_tag][0] +
161  linesize * motion_vector[copy_tag][1];
162  if (bufptr < s->dstbuf) {
163  av_log(s->avctx, AV_LOG_ERROR, "File probably corrupt\n");
164  return AVERROR_INVALIDDATA;
165  }
166 
167  s->dstptr[0] = bufptr[0];
168  s->dstptr[1] = bufptr[1];
169  s->dstptr[linesize] = bufptr[linesize];
170  s->dstptr[linesize + 1] = bufptr[linesize + 1];
171 
172  return 0;
173 }
174 
175 /**
176  * Return the next nibble in sequence, consuming a new byte on the input
177  * only if necessary.
178  */
179  static uint8_t yop_get_next_nibble(YopDecContext *s)
180 {
181  int ret;
182 
183  if (s->low_nibble) {
184  ret = *s->low_nibble & 0xf;
185  s->low_nibble = NULL;
186  }else {
187  s->low_nibble = s->srcptr++;
188  ret = *s->low_nibble >> 4;
189  }
190  return ret;
191 }
192 
193  static int yop_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
194  AVPacket *avpkt)
195 {
196  YopDecContext *s = avctx->priv_data;
197  AVFrame *frame = s->frame;
198  int tag, firstcolor, is_odd_frame;
199  int ret, i, x, y;
200  uint32_t *palette;
201 
202  if (avpkt->size < 4 + 3 * s->num_pal_colors) {
203  av_log(avctx, AV_LOG_ERROR, "Packet too small.\n");
204  return AVERROR_INVALIDDATA;
205  }
206 
207  if ((ret = ff_reget_buffer(avctx, frame)) < 0)
208  return ret;
209 
210  if (!avctx->frame_number)
211  memset(frame->data[1], 0, AVPALETTE_SIZE);
212 
213  s->dstbuf = frame->data[0];
214  s->dstptr = frame->data[0];
215  s->srcptr = avpkt->data + 4;
216  s->src_end = avpkt->data + avpkt->size;
217  s->low_nibble = NULL;
218 
219  is_odd_frame = avpkt->data[0];
220  if(is_odd_frame>1){
221  av_log(avctx, AV_LOG_ERROR, "frame is too odd %d\n", is_odd_frame);
222  return AVERROR_INVALIDDATA;
223  }
224  firstcolor = s->first_color[is_odd_frame];
225  palette = (uint32_t *)frame->data[1];
226 
227  for (i = 0; i < s->num_pal_colors; i++, s->srcptr += 3) {
228  palette[i + firstcolor] = (s->srcptr[0] << 18) |
229  (s->srcptr[1] << 10) |
230  (s->srcptr[2] << 2);
231  palette[i + firstcolor] |= 0xFFU << 24 |
232  (palette[i + firstcolor] >> 6) & 0x30303;
233  }
234 
235  frame->palette_has_changed = 1;
236 
237  for (y = 0; y < avctx->height; y += 2) {
238  for (x = 0; x < avctx->width; x += 2) {
239  if (s->srcptr - avpkt->data >= avpkt->size) {
240  av_log(avctx, AV_LOG_ERROR, "Packet too small.\n");
241  return AVERROR_INVALIDDATA;
242  }
243 
244  tag = yop_get_next_nibble(s);
245 
246  if (tag != 0xf) {
247  ret = yop_paint_block(s, frame->linesize[0], tag);
248  if (ret < 0)
249  return ret;
250  } else {
251  tag = yop_get_next_nibble(s);
252  ret = yop_copy_previous_block(s, frame->linesize[0], tag);
253  if (ret < 0)
254  return ret;
255  }
256  s->dstptr += 2;
257  }
258  s->dstptr += 2*frame->linesize[0] - x;
259  }
260 
261  if ((ret = av_frame_ref(data, s->frame)) < 0)
262  return ret;
263 
264  *got_frame = 1;
265  return avpkt->size;
266 }
267 
268  AVCodec ff_yop_decoder = {
269  .name = "yop",
270  .long_name = NULL_IF_CONFIG_SMALL("Psygnosis YOP Video"),
271  .type = AVMEDIA_TYPE_VIDEO,
272  .id = AV_CODEC_ID_YOP,
273  .priv_data_size = sizeof(YopDecContext),
274  .init = yop_decode_init,
275  .close = yop_decode_close,
276  .decode = yop_decode_frame,
277 };
YopDecContext::srcptr
uint8_t * srcptr
Definition: yop.c:43
copy_tag
static int copy_tag(AVIOContext *in, AVIOContext *out, int32_t tag_name)
Definition: ismindex.c:107
NULL
#define NULL
Definition: coverity.c:32
s
const char * s
Definition: avisynth_c.h:768
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:218
data
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
imgutils.h
misc image utilities
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
yop_get_next_nibble
static uint8_t yop_get_next_nibble(YopDecContext *s)
Return the next nibble in sequence, consuming a new byte on the input only if necessary.
Definition: yop.c:179
YopDecContext
Definition: yop.c:34
AVPacket::size
int size
Definition: avcodec.h:1431
YopDecContext::src_end
uint8_t * src_end
Definition: yop.c:44
YopDecContext::frame_data_length
int frame_data_length
Definition: yop.c:40
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1727
YopDecContext::frame
AVFrame * frame
Definition: yop.c:36
AVCodec
AVCodec.
Definition: avcodec.h:3408
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:42
ff_reget_buffer
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame)
Identical in function to av_frame_make_writable(), except it uses ff_get_buffer() to allocate the buf...
Definition: decode.c:1938
YopDecContext::dstptr
uint8_t * dstptr
Definition: yop.c:45
uint8_t
uint8_t
Definition: audio_convert.c:194
av_cold
#define av_cold
Definition: attributes.h:82
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:189
AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:73
yop_decode_frame
static int yop_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: yop.c:193
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
av_frame_ref
int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
Definition: frame.c:441
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1618
frame
static AVFrame * frame
Definition: demuxing_decoding.c:53
AVPacket::data
uint8_t * data
Definition: avcodec.h:1430
tag
uint32_t tag
Definition: movenc.c:1455
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AV_CODEC_ID_YOP
Definition: avcodec.h:357
U
#define U(x)
Definition: vp56_arith.h:37
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
AVERROR
#define AVERROR(e)
Definition: error.h:43
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
YopDecContext::low_nibble
uint8_t * low_nibble
Definition: yop.c:42
motion_vector
static const int8_t motion_vector[16][2]
Lookup table for copying macroblocks.
Definition: yop.c:73
AVCodec::name
const char * name
Name of the codec implementation.
Definition: avcodec.h:3415
internal.h
common internal API header
av_image_check_size
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
Definition: imgutils.c:282
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:1690
paint_lut
static const uint8_t paint_lut[15][4]
Lookup table for painting macroblocks.
Definition: yop.c:58
ff_yop_decoder
AVCodec ff_yop_decoder
Definition: yop.c:268
AVCodecContext::height
int height
Definition: avcodec.h:1690
avcodec.h
Libavcodec external API header.
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:249
AVCodecContext
main external API structure.
Definition: avcodec.h:1518
yop_decode_close
static av_cold int yop_decode_close(AVCodecContext *avctx)
Definition: yop.c:84
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:1619
yop_paint_block
static int yop_paint_block(YopDecContext *s, int linesize, int tag)
Paint a macroblock using the pattern in paint_lut.
Definition: yop.c:134
AVFrame::palette_has_changed
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:375
YopDecContext::num_pal_colors
int num_pal_colors
Definition: yop.c:38
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:232
YopDecContext::first_color
int first_color[2]
Definition: yop.c:39
yop_copy_previous_block
static int yop_copy_previous_block(YopDecContext *s, int linesize, int copy_tag)
Copy a previously painted macroblock to the current_block.
Definition: yop.c:155
internal.h
common internal api header.
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:1545
yop_decode_init
static av_cold int yop_decode_init(AVCodecContext *avctx)
Definition: yop.c:93
YopDecContext::avctx
AVCodecContext * avctx
Definition: yop.c:35
AVCodecContext::frame_number
int frame_number
Frame counter, set by libavcodec.
Definition: avcodec.h:2204
AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
YopDecContext::dstbuf
uint8_t * dstbuf
Definition: yop.c:46
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1407
for
for(j=16;j >0;--j)
Definition: h264pred_template.c:469
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